Dyeing of textile fibers containing nitrogen



Patented Aug. 31, 1948 A 2,448,448 DYEING OF TEXTILE mans CONTAINING NITROGEN James Hutchison lt iacGregor, Booking, Braintree, England, asslgnor to Courtaulds Limited, London, England, a British company No Drawing. Application November 1, 1946, Serial No. 707,331. In Great Britain June 8, 1942 2 Claims. .(Cl. 8-22) This application is a continuation in part application of Serial No. 494,582, filed July 13, 1943, now abandoned.

This invention relates to the dyeing of textile fibres containing nitrogen, such as wool, silk, casein and nylon, with direct cotton dyestuffs from a neutral bath. While a few direct cotton dyestuffs give shades of excellent fastness to washing and milling on wool, the majority of these dyestuffs have extremely poor allinity for this fibre. It has been suggested to pretreat wool and other animal fibres with certain cationic soaps, such as cetyl pyridinium bromide, to increase the afllnity of these fibres for direct cotton dvestufis from neutral baths.

United States Patent No. 2,238,949 describes a process of treating animal fibres or other lieu-'- tral or artificial fibrous or film-like materials consisting of or containing protein substances or their derivatives or containing basic aminoor imino-groups attached to residues which are not removed from the materials by rinsing with water with a substance, such for example as cyanamide and its dialkyl derivatives, which is adapted to react with an aminoor imino group with obtained by heating cyanourea and an alcoholic solution of methylamine in a sealed tube for 2 hours at 100 centigrade; dimethyl dicyandlamldine, (CHa)2N-C(-NH)NHCONH2, prepared in the same way from cyanourea and dimethylamine; diphenyl dicyandlamidine,

prepared in the same way from cyanourea and diphenylamine; and the tri-beta-hydroxyethyl di- -cyandiamidine obtained by reacting/tlienecesformation of a substituted amidine, the treatment being conducted under sufliclently drastic conditions to result in a detectable chemical reaction. It is stated that such treatment efiects a change in the chemical character and therewith the affinity of the material for various agents such as for instance dyestuffs.

l have now found that I can obtain good dyeings on textile fibres containing nitrogen, such as wool, silk, casein and nylon, with direct cotton dyestuffs from a neutral bath by pretreating the said fibres with an aqueous solution of an amino compound as defined herein, in the presence of a small quantity of free acid.

The amino compounds used according to the present invention are cyanamide, dicyandiamide,

melamine, 'dicyan-diamidine, guanidine, biguanide, alkyl, hydroxyl-alkyl and aryl substituted dicyandiamidines, guanidines and biguanides and the salts of dicyandiamidine, guanidine, blguanide, alkyl, hydroxyalkyl and aryl substituted dicyandiamidines, guanidines and biguanides. The invention does not include the use of products obtained by the interaction of formaldehyde or compounds yielding formaldehyde or sary quantity (3 mols) of ethylene oxide with dicyandiamidine. Examples of substituted guanidines are dimethyl guanidine,

CHa-NH-C (NI-I NHCH:; and trimethyl guanidine,

CHa-NH-C (NCH3) NHCH which are the NN'-'dimethyl guanidine and NN'N"-trimethyl guanidine referred to by T. L. Davis and R. C. Elderfield in the Journal of the American Chemical Society (1932) volume 54, pages 1499-1503; mono-beta-hydroxyethyl guanidine, the hydrochloride of which is prepared by refluxing monoethanolamine and cyanamide in the presence of hydrochloric acid; di-beta-hydroxyethyl guanidine, obtained in a similar manner from diethanolamine and cyanamide; the tri-beta-hydroxyethyl guanidine obtained by the reaction of ethylene oxide (3 mols) on guanidine; monophenyl guanidine as described in the ,Journal of the American Chemical Society (1929) volume 51, page 476; di-ortho-tolyl guanidine, C7H7-NH-C(NH)NHC7H7, diphenyl guanidine, CcH5-NH-C(NH)--NHC:H5, and triphenyl guanidine,

(see for example W. J. S. Naunton, "Journal of the Society of Chemical Industry, 1925, volume 44, pages 243T-247T, and British patent specifications Nos. 223,410 and 262,155). Examples of biguanide derivatives are monomethyl biguanide,

' 3 CHaNHC(NH)-NHC(NH)-NH:. prepared by heating dicyandiamide and an aqueous (25 per cent) solution of methylamine with crystalline copper sulphate under pressure at 95 centigrade; monobetahydroxyethyl biguanide,

HO-CHa-CHe-NH-C (NH) NH-C (NH) NH:;

prepared in the same way using dicyandlamidc and ethanolamine; dimethyl biguanlde,

prepared in the same way using dicyandiamide and dimethylamine; and the triphenyl biguanide prepared by heating dicy-andiamide and aniline hydrochloride in the molar proportions (3 mols) to form the triphenyl compound. Examples of suitable salts are given below.

The acid conveniently be a weak organic acid, such as, for example, acetic acid.

The process is particularly valuable in the dyeing of union fabrics, for example those containing cellulosic fibres, including animalized cellulosic fibres, and animal fibres, particularly wool, since such union fabrics can be dyed in fast solid shades with direct cotton dyestufls in neutral baths.

In carrying out my invention I have found that the wool or other nitrogen-containing fibre can be advantageously treated with 50 volumes of a solution of a guanidine salt, such for instance as the citrate and adipate, or with a guanidine salt of an alkyl ester of an aliphatic dibaslc acid, such as guanidine ethyl oxalate and guenidine octyl succlnate, or with dicyandiamide, or with a dicyandiamidine salt, such as the sulphate thereof, or with a biguanide salt, such as monoethanol biguanide neutral sulphate, or with cyanamide itself, the treatment being carried out in the presence of a small amount of acetic acid, say 2 cubic centimetres of 80 per cent acetic acid in each litre of solution, at the boil for about 30 minutes, and then rinsed, whereupon the dyeing can be carried out in a neutral dyebath. Among the direct cotton dyestuifs which can be employed when carrying out my invention, I may mention:

Chlorazol Fast Orange AGS-Journal of the Society of Dyers and Colourists, 1938, page 270. Diphenyl Brilliant Blue FF-Colour Index No.

518. Chlorazol Black BHSColour Index No. 401.

parts of ethanol for 2 hoursunder a reflux condenser, and after filtering, the ethanol is distilled off and the residue poured into water. The

, aqueous mixture is then extracted with ether to Diphenyl Fast Red 7BLJournal oi. the Society I,

of Dyers and Colourists, 1938, page 273.

Example 1 Dioctyl succlnate is prepared by treating, at a temperature below 20 centigrade, 2 mols of 2- ethyl-hexanol with 1 mol of succinyl chloride, and then heating at 100 centigrade for two hours. 684 parts of dioctyl succlnate are boiled with 180 parts of guanidine carbonate in 2000 remove the z-ethyl-hexanol and the aqueous layer evaporated to dryness when the guanidine octyl succlnate is obtained as a white soapy solid, soluble in water. A length of an all woollen fabric is treated for 30 minutes at the boil in an aqueous solution containing 1 gram of guanidine octyl succinate and 2 cubic centimetres of per cent acetic acid per litre of solution, the liquor to fabric ratio being 50-1. The fabric is then rinsed and immersed in a neutral dyebath at 60 centigrade containing 2 per cent of Diphenyl Brilliant Blue FF (Colour Index No. 518) calculated on the weight of the wool. The temperature of the dyebath is raised in 15 minutes to to centigrade and dyeing continued for one hour at this temperature, whereupon the wool is dyed a full shade of blue, and the bath is practically exhausted. The fastness to light and washing of the dyed fabric is better than that of a similar dyeing on untreated cellulosic material, while untreated wool is merely tinted.

Example 2 2/24s woollen yarn is treated for 30 minutes at the boil in an aqueous solution containing 1 gram of guanidine adipate and 2 cubic centimetres of 80 per cent acetic acid per litre, the liquor to yarn ratio being 50 to 1. The yarn is then rinsed and dyed in accordance with the procedure given in Example 1 in a neutral bath containing 2 per cent of Chlorantine Fast Blue 3G LL, calculated on the weight of the wool. A full shade of blue is obtained and the bath is practically exhausted. Untreated wool when dyed in the same bath is merely tinted.

Example 3 2/24s woollen yarn is treated for 30 minutes in 50 volumes of a boiling 0.5 per cent aqueous solution of mono-beta-hydroxyethyl biguanide neutral sulphate (prepared as described in Example 11 of U. S. patent specification No.

2,223,935), containing 3 cubic centimetres of 80 per cent acetic acid per litre. The yarn is then rinsed and dyed in accordance with the procedure given in Example 1 in a. neutral dyebath containing 2 per cent of Chlorazol Fast Scarlet 4B5, calculated on the weight of the wool. A full shade of scarlet is obtained, and the bath is practically exhausted.

Example 4 Example 5 A length of dress fabric composed of a spun viscose staple fibre warp and a Botany worsted weft is treated for 30 minutes with 50 volumes of a boiling 0.5 per cent aqueous solution of guanidine octyl succlnate containing 2 cubic centimetres of,80 per cent acetic acid per litre. The fabric is then rinsed lightly and dyed with 8 per cent Chlorazol Black BHS and 35 per cent of common salt, based on the weight of the fabric. The salt is added gradually over a period of 20 minutes, while the bath is maintained at a temperature of 60 centigrade. The temperature is then raised to from 95 to 100 centigrade and the dyeing is continued at this temperature for one hour. Both the spun viscose and the wool are dyed to the same depth and a solid navy shade is obtained, which is very fast to washing.

Example 6 A length of an all woollen fabric is treated for 30 minutes at the boil in 50 volumes of an aqueous solution containing 1 gram of guanidine cetyl succinate (prepared as described in Example 5 of my co-pending British patent specification No. 558,892) and 2 cubic centimetres of 80 per cent acetic acid per litre. The fabric is then rinsed and dyed in accordance with the procedure given in Example 1 in a neutral bath containing 2 per cent of Diphenyl Fast Red 'IBL, calculated on the weight of the wool. The wool is dyed a full sh'ade of red and the bath is almost entirely exhausted. The fastness to light and to washing of the so dyed wool is distinctly better than that of a similar dyeing with Diphenyl Fast Red 7BL on untreated viscose fabric.

Example 7 A length of an all woollen fabric is treated for 30 minutes at the boil in 50 volumes of an aqueous solution containing 10 cubic centimetres of a 50 per cent cyanamide solution and 2 cubic centimetres of 80 per cent acetic acid per litre. The fabric is then rinsed and dyed in accordance with the procedure given in Example 1 in a neutral bath containing 2 per cent of Diphenyl Fast Red 'ZBL, based on the weight of the wool. The wool is dyed a full shade of red and the bath is almost entirely exhausted, while the fastness to washing of the dyeing is better than that of a similar dyeing of Diphenyl Fast Red 7BL on untreated viscose fabric.

What I claim is:

1. A process of dyeing nitrogenous textile fibres which comprises treating the said fibres with an aqueous solution containing a small quantity of free acid and a compound selected from the group consisting of cyanamide, dicyandiamide, melamine, dicyandiamidine, guanidine, biguanide, alkyl, h'ydroxyalkyl and aryl substituted dicyandiamidines, guanidines and biguanides, and salts of dicyandiamidine, guanidine, biguanide and the alkyl, hydroxyalkyl and aryl substituted dicyandiamidines, guanidines and biguanides, and dyeing the thus-treated fibres with a direct cotton dyestuff from a neutral bath,

2. A process of dyeing union fabrics containing nitrogenous and cellulosic fibres which comprises treating the said fabric with an aqueous solution containing a small quantity of free acid and a compound selected from the group consisting of cyanamide, dicyandiamide, melamine, dicyandiamidine, guanidine, biguanide alkyl, hydroxyalkyl and aryl substituted dicyandiamldines, guanidines and biguanides, and salts of dicyandiamidine, guanidine, biguanide and the alkyl, h'ydroxyalkyl and aryl substituted dicyandiamidines, guanidines and biguanides, and dyeing the thus-treated fabric with a direct cotton dyestuil from a neutral bath.

JAMES HUTCHISON MACGREGOR.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,121,337 Brodersen June 21, 1938 2,189,918 Moncrieif Feb. 13, 1940 2,238,949 Schlack Apr. 22, 1941 2,246,070 Schlack June 17, 1941 

